The Republican presidential candidates will debate at the Ronald Reagan library Wednesday, and you can't help but wonder what the Gipper would think of this bunch.

Would that sound you hear at the start of the debate be Reagan rolling over in his nearby grave as each candidate tries to cozy up?

Nobody knows. But as someone who covered him for 20 years in Sacramento and Washington, I can guess.

Reagan probably would be enjoying the show — not just this event in Simi Valley, but the overall campaign circus — and be especially curious about the barker, Donald Trump.

The former president and governor would also probably be wishing he could run in this scattered field. Its huge size — 16 — reflects a party leadership vacuum that he'd quickly fill, chasing off all but a small handful of wannabes.

"That was the idea," CNN President Jeff Zucker said last week. "This is Round 2 of a heavyweight bout."

Or the second episode of a wildly...

If the commercials promoting CNN's Republican primary debate Wednesday make it look like a highly anticipated pay-per-view boxing event, it means they're working.

"That was the idea," CNN President Jeff Zucker said last week. "This is Round 2 of a heavyweight bout."

Or the second episode of a wildly...

(Stephen Battaglio)

But Reagan's secret to success in office — something many in the party have never understood — is that he often governed in pastels, as a pragmatist. He raised taxes or lowered them as he felt was needed. He never hesitated to negotiate with Democrats — or commies.

He's the most environmental governor in California history — protecting wild rivers from dams, preserving a Sierra wilderness by blocking highway builders, creating an air resources board that led to the nation's first auto smog controls.

As governor, he signed legislation allowing collective bargaining for local government workers. Think about that, Gov. Scott Walker of Wisconsin.

What Reagan would not admire about Trump — would be repulsed by— are his bombast and insults. Reagan didn't care for blowhards. The Gipper used tough words — "Tear down this wall" — but was always dignified and gracious, especially in public. The Donald carries on like he needs anger management.

If Reagan got a little personal, he did it with humor, as in gently jabbing his 1980 opponent, President Carter: "Anyone who says he likes cold showers will lie about other things too."

"Reagan would have never called people stupid even if he thought they were," George Steffes, his legislative lobbyist in Sacramento, told me.

Reagan, unlike Trump, definitely would not be calling any woman a fat pig, dog or slob. And unlike Trump, he would not question whether Sen. John McCain (R-Ariz.) was a war hero. He idolized McCain's military service. Nor, unlike Trump, would he characterize Mexicans who migrated here illegally as rapists and drug runners, or vow to deport all 11 million. As president, after all, he signed an amnesty law.

But there are other Republicans running, many of them civilly. One problem for them is that Trump has been sucking up most of the media oxygen and they're gasping for air.

I called some old Reagan hands and watchers to ask them how he'd be sizing up the candidates.

"I've always been hesitant to guess what Reagan would do or think," said Stu Spencer, chief strategist of his successful campaigns for governor and president. "Here's a guy who went to Sacramento and signed the most liberal abortion law in America. He was a very tough guy to peg."

That said, Spencer figured that concerning Trump, "Reagan would just smile and shake his head."

Political strategist Ken Khachigian, who wrote major presidential speeches for Reagan, said "he would be alternately bemused and in some ways troubled. He'd chuckle at so many running.

"But he'd be troubled that we've reached the stage where there are no logical five or six heavyweights who have worked their way up the ranks to run. He'd see this as a party not focused enough to keep some of these people out of the race."

Khachigian added: "He'd probably have some joke to deal with it. He'd come up with something like 'cheaper by the dozen,' out of an old movie. Then he'd go back and ride his horse."

Journalist and biographer Lou Cannon, who has written several books about the GOP icon, said "the Reagan library has become like a cathedral where these guys have to come to pay homage to the Gipper. It's kind of a secular shrine.

"But if you gave most of them a test on what Reagan did, they wouldn't have a clue."

Cannon said he'll go to the debate and "count how many times they bring up Reagan. Anybody who does not compare themselves to Reagan, they win the prize."

I'll be looking for intellectual honesty, knowledge and civility.

But maybe all that's too high a bar. A good show will suffice for now.